Routeguru was the early entrant in landmark based driving direction service and while, several other companies followed (like Yahoo) the ‘route’, none of them were able to create a useful service (all of them had a regional strength and lacked pan India presence).
Google took the UGC approach earlier (with Map Maker) and even launched driving directions service, few months back. The company has now launched landmark based driving service (and also included navigational landmarks on mobile phone), which is primarily driven by the data collected via map maker service.
This effort was possible thanks to the large amount of landmark data that users like you contributed through Google Map Maker. Our new algorithm determines from available signals, which of these landmarks are most useful for navigation, based on importance and closeness to the turns that you’re making. We now combine landmark data, counted turns ("the 2nd right"), intersection names, and road names, and try to use whatever information is most relevant and useful for the direction you’re heading in. – official blog